Thermal Design of Condensers

Gloyer, W. (1970) Hydro. Proc. 49 (July) 107. Thermal design of mixed vapor condensers. 

Kenneth J. Bell, Ph.D., P E., Regents Professor Emeritus, School of Chemical Engineering, Oklahoma State University Member, American Institute of Chemical Engineers. (Thermal Design of Heat Exchangers, Condenser, Reboilers)... 

The prior and substantial contributions of Frank L. Rubin (Section Editor, Sixth Edition) and Dr. Kenneth J. Bell (Thermal Design of Heat Exchangers, Condensers, Reboilers), Dr. Thomas M. Elynn (Cryogenic Processes), and E. C. Standiford (Thermal Design of Evaporators, Evaporators), who were authors for the Seventh Edition, are gratefully acknowledged. 

Table condensed from R. K. Shah and A. Pignotti, Basic Thermal Design of Heat Exchangers National Science Foundation Report, Int-8601771,1988. In this table, all variables except Pu Ru NTUf, and Fare local or dummy variables not necessarily related to those defined in the nomenclature. 

Primary objectives for accomplishing the condensation process vary depending on a particular application, but common features of a vapor-liquid phase-change lead to certain general similarities in thermal design procedure. Nonetheless, thermal design of a condenser does not necessarily follow a standardized procedure, and it greatly depends on a condenser type and the factors mentioned above. 

Thermal and mechanical design of heat exchangers (condensers and evaporators) is presented earlier in this section. 

Successful flue design involves the balancing of the draft against the resistance, possibly for a range of thermal inputs, the avoidance of condensation, and a location of the terminal that ensures unrestricted dispersion of the flue products. 

Although the thermal efficiencies of various mechanical vacuum pumps and even steam jet ejectors vary with each manufacturer s design and even size, the curves of Figure 6-34 present a reasonable relative relationship between the types of equipment. Steam jets shown are used for surf ace intercondensers with 70°F cooling water. For non-condensing ejectors, the efficiency would be lower. 

Design a shell-and-tube reactor that has a volume of 24 m and evaluate its performance as the reactor element in the process of Example 6.2. Use tubes with an i.d. of 0.0254m and a length of 5m. Assume components A, B, and C all have a specific heat of 1.9 kJ/(kg-K) and a thermal conductivity of 0.15W/(m-K). Assume 7 ,>, = 70°C. Run the reaction on the tube side and assume that the shell-side temperature is constant (e.g., use condensing steam). Do the consecutive, endothermic case. 

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